How to be a GOOD web/network programmer in c++

I have been learning c++ for two years at my school and have to admit that there are very few people who work with c++. Thats why i ONLY learn standarts of c++ (11/14/17) but unfortunately did NOT do some real projects. Im really interested in network/backend programming and wanted to use c++ in them. But some people say that building backend web app is horrible and stupid in c++. If this is true what about facebook as i believe it uses c++ largely google chrome, and there is boost.asio and QtNetwork and Wt web framework. Because i am a schoolboy and i ONLY know standarts + boost + some Qt i dont understand what to do next so im tired of learning but not doing anything. Please can you direct me what to do next i mean with boost.asio(boost.beast) and Qt in network programming? What should i do as a c++ programmer in network/web/backend programming?????